69 lines
1.7 KiB
C
69 lines
1.7 KiB
C
/* Signature verification with an asymmetric key
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*
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* See Documentation/security/asymmetric-keys.txt
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*
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* Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#define pr_fmt(fmt) "SIG: "fmt
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#include <keys/asymmetric-subtype.h>
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#include <linux/export.h>
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#include <linux/err.h>
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#include <linux/slab.h>
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#include <crypto/public_key.h>
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#include "asymmetric_keys.h"
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/*
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* Destroy a public key signature.
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*/
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void public_key_signature_free(struct public_key_signature *sig)
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{
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int i;
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if (sig) {
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for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++)
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kfree(sig->auth_ids[i]);
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kfree(sig->s);
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kfree(sig->digest);
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kfree(sig);
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}
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}
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EXPORT_SYMBOL_GPL(public_key_signature_free);
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/**
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* verify_signature - Initiate the use of an asymmetric key to verify a signature
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* @key: The asymmetric key to verify against
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* @sig: The signature to check
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*
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* Returns 0 if successful or else an error.
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*/
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int verify_signature(const struct key *key,
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const struct public_key_signature *sig)
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{
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const struct asymmetric_key_subtype *subtype;
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int ret;
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pr_devel("==>%s()\n", __func__);
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if (key->type != &key_type_asymmetric)
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return -EINVAL;
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subtype = asymmetric_key_subtype(key);
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if (!subtype ||
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!key->payload.data[0])
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return -EINVAL;
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if (!subtype->verify_signature)
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return -ENOTSUPP;
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ret = subtype->verify_signature(key, sig);
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pr_devel("<==%s() = %d\n", __func__, ret);
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return ret;
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}
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EXPORT_SYMBOL_GPL(verify_signature);
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